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Europe Test Crash of Ford Focus at 120 MPH

Focus Immediately Before Impact

Focus Immediately Before Impact

The European TV show Fifth Gear had the Transportation Research Laboratory (TRL) crash a Ford Focus at 120 mph.

This staged crash test represents a worst case collision scenario where the car impacts a rigid, non-deformable, barrier.

After impact you will see the non-flammable Stoddard Test Fluid coming out of the fuel tank. The test fluid is put there to test fuel tank physical integrity.

Here is link to Fifth Gear Video: 

httpv://www.youtube.com/watch?v=6dI5ewOmHPQ

Here are calculations associated with 40 mph and 120 mph collisions. The 120 mph collision has 9 times the energy of a 40 mph collision.

Note that with this equation the energy goes up with the square of the speed, which means that there is 4 times as much energy at 40 mph than 20 mph (40×40= 1600 and 20×20=400).

You can clearly notice that your car takes a lot longer to stop from 60 or 70 mph than from 40 mph because of the square the speed energy issue. To simplify the calculation some more, if you square 60 = 3600 and the square of 40 = 1600 so there is more than twice the energy at 60 than 40.

With 10 the square is 100 and 15 the square is 225. Auto crash testing is typically conducted at speeds up to 40 mph (40×40=1600). There is 16 times as much energy at 40 than 10.

Remember to drive safely. The reality associated with the math applies every time you get behind the wheel.

Ford Recall Cruise Control

Ford Recalls 4.5 Million Cars & Trucks

It’s back in the news again.  This is a serious problem and it is a problem that needs to be corrected once and for all.  From the position of a forensic vehicle expert, that has been involved with product defects for decades, this is not a new problem.

There will always be problems.  Design and product engineering try and make the car and components as reliable as possible.  Unfortunately, some problems seem almost impossible to get rid of.

Problems get into a system, initially, in the form of a design defect.  Design defects mean that each and every car built,with that technology,is flawed.  From a forensic point of view, it is much easier to prove a manufacturing defect which only affects one vehicle.

This recall extends by an additional 4.5 million vehicles Ford’s efforts to eliminate a fire hazard in a faulty cruise-control deactivation switch made by Texas Instruments.  With Tuesday’s decision 16 million Ford cars and trucks have now been recalled since 1999 due to the switch according to the National Highway Traffic Safety Administration.  A very thorough example of an investigation report can be found here.

Design Defect Discussion

It is interesting to analyze the historical evolution of automobile parts.  When you analyze a vehicle component failure there is lots of history to review.  This history can be extremely complex but the story and evolution of the part will eventually unfold.

Seat Failure Analysis

One example is a car seat failure.  In a rear end impact the driver’s seat collapsed, the driver slid backwards underneath the seatbelt and their neck was broken when they impacted the rear seat in a horizontal manner.  It was possible to do a great deal of collision analysis and calculate impact speeds, and forces applicable to the failure and injury sustained.

Plaintiff attorney Request For Production to the OEM resulted in boxes of documents provided under Protective Order.  Research showed evolution of the seat design going back over 20 years.

In this accident the seat failed below its failure strength.  According to FMVSS the seat has to withstand a force of 20 times the weight of the seat back.  There is no thing about driver or passenger in the equation.  If the seat back weighs 10 pounds then the seat back has to withstand 200 pounds of deflective force.  This is all clearly spelled out in the Standard.

In the subject seat, I had the seat mechanism X Ray photographed so that I knew exactly what the failure was before going forward with the plaintiff attorney.

Defects can be deadly.  If you have concerns go to the NHTSA site and spend some time.  It can be very educational.  The TREAD Acthas put heavy penalties on manufacturers that knowingly permit tgheir products to fail. 

There is lots of legal rhetoric in the area of design defect, manufacturing defect, accident, injury, causation, maintenance, and negligence.  Determination of a proximate cause can be very difficult, especially if the part burns up and is consumed in the fire.

SAE – The “Society of Automotive Engineers”

A Universe of Automotive Societies

Automobile design, manufacturing, maintenance, and disposal historically account for about 4% of the Gross Domestic Product of the US.  Contemporary acknowledgement of the significance of the “Car Business” is well documented in a 2003 report to the Alliance of Automobile Manufacturers.  Since the Car Business is such big business there are many very important professional societies involved with transportation.  This post will provide some relevant background that may be of interest to the Automotive Tribune reader so that you can consider beneficial or educational affiliation.

Society of Automotive Engineers – SAE

sae1SAE is the professional society for transportation engineers involved in space, aviation, highway, off-highway, and marine transportation.  SAE membership is around 80,000 worldwide from all of the disciplines and professions that are involved in automotives professionally.  Not all members of SAE are Engineers but all members are Professionals.  A good historical background is found on the SAE web site and here are a couple of significant paragraphs from that text.

In the early 1900s there were dozens of automobile manufacturers in the United States, and many more worldwide. Many of these manufacturers and automobile parts companies joined trade groups that met their needs for promoting business and raising public awareness of this new form of transportation. A need for patent protection, common technical design problems, and the development of engineering standards was quickly emerging, however, and many engineers in the automobile business expressed a desire to have “free exchange of ideas” in order to expand their individual technical knowledge base.

By 1916 the Society of Automobile Engineers membership had grown to 1,800. At the annual meeting that year representatives from the American Society of Aeronautic Engineers, the Society of Tractor Engineers, as well as representatives from the power boating industry made a pitch to SAE for oversight of technical standards in their industries. Aeronautics was a fledgling industry at that time, and few could have been expected to know the essential role it would take in world history in a very short time. Early supporters of the concept of a society to represent aeronautical engineers were Thomas Edison, Glenn Curtiss, Glenn Martin, and Orville Wright.

Out of that fateful meeting in 1916 came a new organization with new horizons. This was to be a new society representing engineers in all types of mobility-related professions. SAE member Elmer Sperry actually created the term “automotive” from Greek autos (self), and Latin motivus (of motion) origins to represent any form of self powered vehicle. The Society of Automobile Engineers became the Society of Automotive Engineers, and the most important chapter in the SAE saga was underway.

SAE International

 There is a great deal of activity in SAE and this post, in no way, addresses all of the educational activities to international relationships.  However, if you are interested in a professional level of interaction then spend some time researching the SAE Web Site.

Collision Gallery Photographs

Collision Gallery

buick-wagon-side-impact-frontCheck out the Collision Gallery.  It contains interesting and educational photographs of collision vehicles and components.  Each picture tells a story related to the collision phases of: pre-crash, impact, and post impact for the driver, vehicle and environment.

buick-wagon-side-impact-rear-1Automotive Tribune has a substantial forensic photographic library.  If you have an interest in a particular type of vehicle or collision event including pedestrian, skateboard, tree, tractor trailer, sports car, SUV, motorcycle, trailer, commercial machinery, golf carts, guard rails, lift gates, tires, lights, brakes, wheels, axles, fire, maintenance, towing, vehicle recovery, aerial photographs, damage documentation, overloading, pavement drop-off, component failure or collision analysis let us know and the photos will be added to the gallery.

Post Crash Analysis For Unrestrained Occupants

front-seat-deformationSeat belts are an important part of the safety systems in carsTo a trained investigator review of a Traffic Crash Report, site visit, and inspection of the vehicles can answer many questions about the technical nature of the impact.

In this analysis the objective is to provide a thorough identification of steps associated with arriving at impact speeds and assessment of seat belt usage for front and rear passengers.

approach-to-impactScale diagram Prepared

for Impact and Final Rest vehicle positions. Inspection of the crash site permitted final rest placement for the Mercury. Final rest position was not identified on the Crash Report and no specific evidence at the crash site permitted placement of the Honda at final rest. … Continue Reading

Motor Vehicle Accident Reconstruction & Biomechanical Physics – Part 3

Aerial Crush Photography 

dsc_0088-largeOn-site aerial photographs taken with the aid of a boom and perimeter grid capture collision data. This system has proven to be extremely useful in addressing collision dynamics.A brief synopsis of this method reveals its usefulness to the accident reconstructionist and biomechanical expert. 

aerial-boom-being-raised-over-carHorizontal lines for the red car illustrate 1′ of interior crush to the impact side-bar beam in the door and 1.5′ of collapse in the vehicle roof structure.  Also, shown on the opposite side of the car is a general bowing of the vehicle structure showing how impact forces are transmitted throughout the vehicle. … Continue Reading